Researchers using NASA laser technology have discovered thousands of new ancient structures at the Mayan city of Caracol, Belize. The data, which would have taken 25 years to collect using traditional archaeological methods, was gathered in only four days by using a technique called LiDAR (Light Detection and Ranging).

Until now, exploring large ancient Maya sites was challenging and time consuming. Most structures or features are hidden within heavily forested and hilly terrain and are difficult to record.

Airborne LiDAR made research significantly easier, and faster, allowing researchers to see 'beyond the rainforest'. Laser beams emitted from a plane were able to penetrate the thick canopy that covers the site to reach sensors on the ground. The laser survey then produced images of the ancient settlement and its surroundings, covering a 200 square kilometre radius in just four days.

“It is very exciting,” said Arlen Chase, Anthropology Professor at the University of Central Florida, where the data is being analysed. “The images not only reveal topography and built features, but also demonstrate the integration of residential groups, monumental architecture, roadways and agricultural terraces, vividly illustrating a complete communication, transportation and subsistence system.”

The results of the LiDAR mapping project in Caracol are significant. Eleven new causeways, five new causeway termini, tens of thousands of agricultural terraces and many hidden caves were located. The survey data was also used to confirm previous estimates of the size of the settlement and population: Caracol was spread out over 177 square kilometres, with at least 115,000 residents in 650 AD.

Researchers are hoping that now Caracol's entire landscape is recreated virtually as a 3D model, this could expand our understanding of the Maya empire and civilization, and perhaps offer clues to what may have caused its destruction.